86 scottsdale sm465 tranny noise

[8swbk10]

hey guys i just got my truck inspected and the first day on the road it was fine for about 15 minutes then all of a sudden when i let off the gas it makes a loud howling noise it only happens when i let off the gas but if i push in the clutch it goes away. i checked the clutch fluid and tranny fluid and theyre fine. can it be the clutch, pressure plate or throw out bearing? or maybe even the transfercase? im pretty sure the s clutch , pressure plate and t.o.b are stock. when i did a engine swap in 08 we did not change any of them because they looked great. i can't debunk what the noise is and i dont want to rip everything apart yet with out knowing exactly what it is any help would be greatly appreciated thanks

[8swbk10]

anyoneee?

[Keith Seymore]

Could be rear axle as well; axle whine can occur on drive, float, or coast.

Make sure it's not coming from the axle before you start tearing into the trans (which seems less likely to me).

K

[silverbullet01]

x2 on the rear end, especially on the 10 bolts like in your 86 if its a half ton, we have a 86 4x4 with 700r4 and the rear end howls really bad when your on the gas but goes away as soon as you let off the gas.

[Telecasterjoey]

Originally Posted by silverbullet01

x2 on the rear end, especially on the 10 bolts like in your 86 if its a half ton, we have a 86 4x4 with 700r4 and the rear end howls really bad when your on the gas but goes away as soon as you let off the gas.

mine does the same thing how long till it goes lol?

[8swbk10]

yup theyre 10 bolts with 3.08 gears. it only makes the noise when i let off the the gas and then if i push in the clutch it goes away so thats what had me thinking it might be something in the tranny or tcase. but i still need to check the rear and front diffs out anyway. 2 nights ago was the first time the truck was driven on the road since like 2001 so im just finding more things out now. the last thing i wanna do is pull the engine and tranny again and if its the rears my friend has a set of 8lugs with 4.10 gears that ill pick up. thanks for the answers ill check out the rears tommarow when i do the brakes

[Phillip Pennartz]

Could throwout bearing.

mine did that

[silverbullet01]

when you shove the clutch it takes thes strain off the rear end and it stops howling.. if it was a throwvout bearing i would think it would do it all the time with the clutch out. even in neautral.
Posted via Mobile Device

[silverbullet01]

haha. all depends. thats rear end number 2 in that truck alone. not to mention how many my 84 scottsdale street truck has ate.. if you dont poubd it to bad it will last quite a while. its just the gears notvmeshing quite right. the issue with mine is the pinion has slack in it and its not shimmed quite right.
Posted via Mobile Device

[Wrecked1982]

my 81 C30 does THE EXACT SAME THING finaly im not the only one, i have the same transmission and whenever i let the fuel off no matther in witch gear (noise increase depending in what gear its in). i suspect internal tranny bearings are shot it has 225 000+km and there are no synchros left what so ever gotta match rev or it wont shift at all. i gave up on finding where its from i drove it a full year like that and now it became a donor truck

[8swbk10]

dam i hope its not the tranny bearings hopefully its the rear end..alot easies to swap out and find then one of these trannys

[8swbk10]

hahahaha im a dumbass..i was so excited to drive my truck since it finally had a inspection that i forgot to check all my fluids like i should have and my rear diff was bone dry..atleast i know to check everything next time instead of pulling my hair out trying to figure out what the noise is..thanks for all the responses though i apreciate them

[Keith Seymore]

Originally Posted by 8swbk10

hahahaha im a dumbass..i was so excited to drive my truck since it finally had a inspection that i forgot to check all my fluids like i should have and my rear diff was bone dry..

Yep - that'd do it....

[sethv]

At least you didn't drive it too much and kill the rear end!!

[bowtiemanchevyman]

i still would replace the axel with your friends just for the gears 3.08 suck so bad. they are all a stronger axle for you, you already put two rear end in there so you may want to put a stronger on in there for you.